The event handler receives an argument of type DevExpress.XtraBars.Navigation.NavigationPeekFormButtonClickEventArgs containing data related to this event.
The Peek Form (see ShowPeekFormOnItemHover) can display custom buttons at its top or bottom edge. These buttons have a flat appearance and are painted based on the current skin. To create and show these buttons, add buttons to the FlyoutPanelButtonOptions.Buttons collection and enable the FlyoutPanelButtonOptions.ShowButtonPanel option. These properties and other properties related to the button panel display are accessible via the OptionsPeekFormButtonPanel object.
To respond to button clicking, handle the PeekFormButtonClick event.